Changing the premise to "superintelligence is the only thing that can save us" doesn’t invalidate the logic of being cautious. It just shifts the debate to which risk is more plausible. The reasoning about managing existential risks remains valid either way, the real question is which scenario is more likely, not whether the risk-based logic is flawed.
Just like with nuclear power, which can be both beneficial and dangerous, we need to be careful in how we develop and control powerful technologies. The recent deregulation by the US admin are an example of us doing the contrary currently.